Gas phase kinetics of CVD precursors

有机化合物，如二茂铁或乙酰丙酮铝，用于从气相制备薄膜和颗粒。在大多数情况下，气相中的反应动力学没有得到很好的研究，这使得合理的工艺规划变得困难甚至不可能。在第一个项目阶段，研究了三种典型的重要CVD前体在气相中的热分解。借助最新的同步辐射质谱方法（i2 PEPICO），可以更好地确定惰性气体中转化的反应机理，并确定了第一动力学参数。调查发生在流动反应器中，使用流体力学模拟进行了优化;还使用CFD模拟确定了微反应器的温度场和停留时间。在本报告的延续期内，研究的CVD前体与其他反应伙伴（如水蒸气、乙烯或氢气）的反应是关注的焦点，因为这些反应伙伴通常用于气相合成工艺。这些反应的动力学参数和反应级数将在很宽的参数范围内进行研究。在这里，代理模型的开发，它允许调整和提取的Arcidius参数没有（有缺陷的）假设的一维。此外，反应器中的体积与表面积的比率将系统地变化，以能够明确地确定有机金属化合物的反应中气相反应的份额。其目标是，一方面在项目期结束前确定可靠的反应参数和反应机制，另一方面在评价真实的流动动力学数据方面取得方法上的进展。

Organometallic compounds, such as ferrocene or aluminium acetylacetonate, are used to produce thin films and particles from the gas phase. For the most part, the reaction kinetics in the gas phase are not well studied, which makes rational process planning difficult or even impossible. In the first project phase, the thermal decomposition of three exemplary and important CVD precursors in the gas phase was investigated. With the help of the latest synchrotron-based mass spectrometric methods (i2PEPICO), the reaction mechanism for the conversion in inert gases could be determined much better and the first kinetic parameters were determined. The investigations took place in flow reactors, which were optimised using fluid mechanics simulations; temperature fields and residence times were also determined for microreactors using CFD simulations. In the continuation period applied for here, the reactions of the investigated CVD precursors with other reaction partners, such as water vapour, ethylene or hydrogen, are the focus of interest, as these are often used in gas-phase synthesis processes. Kinetic parameters and the reaction order of these reactions are to be investigated in a wide parameter range. Here, surrogate models are developed, which allow the adjustment and extraction of the Arrhenius parameters without the (flawed) assumption of one-dimensionality. In addition, the ratio of volume to surface area in the reactor will be systematically varied to be able to explicitly determine the share of the gas phase reactions in the reactions of the organometallic compounds. The goals are, on the one hand, to determine reliable reaction parameters and reaction mechanisms by the end of the project period and, on the other hand, to achieve methodological progress in the evaluation of kinetic data in real flows.